Remove hardcoded example string from menu component

DONE, but there is still a little issue in menu component:

    <li class="mzp-c-menu-category mzp-has-drop-down mzp-js-expandable">
      {% set url = item.url|default(item_attributes.href|default("#")) %}
      <a{{ item_attributes.setAttribute('aria-haspopup', 'true').setAttribute('href', url) }}>{{ item.title }}</a>
        {{ panels }}
    </li> 

Panels need to be inside a menu item to works. It will create issues because:

• Some menu items has no panels
• "panels" variable contains all panels